Introduce a new event: onLayerChange

NEWS.md

@@ -79,6 +79,10 @@ The [Cycle](doc/plugin/Cycle.md) plugin has much better support for cycling thro
 
 There are situations where one would like to disable sending a report after each and every step of a macro, and rather have direct control over when reports are sent. The new `WITH_EXPLICIT_REPORT`, `WITH_IMPLICIT_REPORT` and `SEND_REPORT` steps help with that. Please see the [Macros](doc/plugin/Macros.md) documentation for more information.
 
+### Events now trigger on layer changes
+
+Changing layers now triggers the `onLayerChange` event - but only if there was real change (thus, calling `Layer.on(SOME_LAYER)` multiple times in a row will only trigger one event). This event was introduced to help plugins that depend on layer state schedule their work better.
+
 ## New hardware support
 
 Kaleidoscope has been ported to the following devices:

src/kaleidoscope/event_handlers.h

@@ -71,6 +71,12 @@
                 (const char *command),                                    __NL__ \
                 (command), ##__VA_ARGS__)                                 __NL__ \
                                                                           __NL__ \
+   /* Called when the layer state changes. Which layes changed are    */  __NL__ \
+   /* not passed as arguments. If one needs that info, they should    */  __NL__ \
+   /* track Layer.getState() themselves.                              */  __NL__ \
+   OPERATION(onLayerChange,                                               __NL__ \
+                _NOT_ABORTABLE,                                           __NL__ \
+                (), (), ##__VA_ARGS__)                                    __NL__ \
    /* Called before reporting our state to the host. This is the       */ __NL__ \
    /* last point in a cycle where a plugin can alter what gets         */ __NL__ \
    /* reported to the host.                                            */ __NL__ \

src/kaleidoscope/hooks.h

@@ -32,6 +32,9 @@ extern void handleKeyswitchEvent(kaleidoscope::Key mappedKey, byte row, byte col
 
 namespace kaleidoscope {
 
+// Forward declaration to enable friend declarations.
+class Layer_;
+
 // The reason why the hook routing entry point functions live within
 // class Hooks and not directly within a namespace is, that we want
 // to restrict who is allowed to trigger hooks, mainly to prevent
@@ -49,6 +52,7 @@ class Hooks {
   // Kaleidoscope_ calls Hooks::onSetup, Hooks::beforeReportingState
   // and Hooks::afterEachCycle.
   friend class Kaleidoscope_;
+  friend class ::kaleidoscope::Layer_;
 
   // ::handleKeyswitchEvent(...) calls Hooks::onKeyswitchEvent.
   friend void ::handleKeyswitchEvent(kaleidoscope::Key mappedKey,

src/kaleidoscope/layers.cpp

@@ -168,6 +168,8 @@ void Layer_::on(uint8_t layer) {
   // Update the keymap cache (but not liveCompositeKeymap; that gets
   // updated separately, when keys toggle on or off. See layers.h)
   updateActiveLayers();
+
+  kaleidoscope::Hooks::onLayerChange();
 }
 
 // Deactivate a given layer
@@ -187,6 +189,8 @@ void Layer_::off(uint8_t layer) {
   // Update the keymap cache (but not liveCompositeKeymap; that gets
   // updated separately, when keys toggle on or off. See layers.h)
   updateActiveLayers();
+
+  kaleidoscope::Hooks::onLayerChange();
 }
 
 boolean Layer_::isOn(uint8_t layer) {

src/kaleidoscope/plugin/Colormap.cpp

@@ -28,7 +28,7 @@ namespace plugin {
 
 uint16_t ColormapEffect::map_base_;
 uint8_t ColormapEffect::max_layers_;
-uint8_t ColormapEffect::last_highest_layer_;
+uint8_t ColormapEffect::top_layer_;
 
 void ColormapEffect::max_layers(uint8_t max_) {
   if (map_base_ != 0)
@@ -42,21 +42,20 @@ void ColormapEffect::onActivate(void) {
   if (!Kaleidoscope.has_leds)
     return;
 
-  last_highest_layer_ = Layer.top();
-  if (last_highest_layer_ <= max_layers_)
-    ::LEDPaletteTheme.updateHandler(map_base_, last_highest_layer_);
+  top_layer_ = Layer.top();
+  if (top_layer_ <= max_layers_)
+    ::LEDPaletteTheme.updateHandler(map_base_, top_layer_);
 }
 
-void ColormapEffect::update(void) {
-  if (!Kaleidoscope.has_leds || Layer.top() == last_highest_layer_)
-    return;
-
-  onActivate();
+void ColormapEffect::refreshAt(byte row, byte col) {
+  if (top_layer_ <= max_layers_)
+    ::LEDPaletteTheme.refreshAt(map_base_, top_layer_, row, col);
 }
 
-void ColormapEffect::refreshAt(byte row, byte col) {
-  if (last_highest_layer_ <= max_layers_)
-    ::LEDPaletteTheme.refreshAt(map_base_, last_highest_layer_, row, col);
+EventHandlerResult ColormapEffect::onLayerChange() {
+  if (::LEDControl.get_mode() == this)
+    onActivate();
+  return EventHandlerResult::OK;
 }
 
 EventHandlerResult ColormapEffect::onFocusEvent(const char *command) {

src/kaleidoscope/plugin/Colormap.h

@@ -28,15 +28,15 @@ class ColormapEffect : public LEDMode {
 
   void max_layers(uint8_t max_);
 
+  EventHandlerResult onLayerChange();
   EventHandlerResult onFocusEvent(const char *command);
 
  protected:
   void onActivate(void) final;
-  void update(void) final;
   void refreshAt(byte row, byte col) final;
 
  private:
-  static uint8_t last_highest_layer_;
+  static uint8_t top_layer_;
   static uint8_t max_layers_;
   static uint16_t map_base_;
 };

src/kaleidoscope/plugin/LED-ActiveModColor.cpp

@@ -22,48 +22,72 @@
 namespace kaleidoscope {
 namespace plugin {
 
+uint8_t ActiveModColorEffect::mod_keys_[MAX_MODS_PER_LAYER];
+uint8_t ActiveModColorEffect::mod_key_count_;
+
 cRGB ActiveModColorEffect::highlight_color = (cRGB) {
   0xff, 0xff, 0xff
 };
 
 cRGB ActiveModColorEffect::sticky_color = CRGB(0xff, 0x00, 0x00);
 
-EventHandlerResult ActiveModColorEffect::beforeReportingState() {
+EventHandlerResult ActiveModColorEffect::onLayerChange() {
   if (!Kaleidoscope.has_leds)
     return EventHandlerResult::OK;
 
+  mod_key_count_ = 0;
+
   for (byte r = 0; r < ROWS; r++) {
     for (byte c = 0; c < COLS; c++) {
-      Key k = Layer.lookupOnActiveLayer(r, c);
-
-      if (::OneShot.isOneShotKey(k)) {
-        if (::OneShot.isSticky(k))
-          ::LEDControl.setCrgbAt(r, c, sticky_color);
-        else if (::OneShot.isActive(k))
-          ::LEDControl.setCrgbAt(r, c, highlight_color);
-        else
-          ::LEDControl.refreshAt(r, c);
-      } else if (k.raw >= Key_LeftControl.raw && k.raw <= Key_RightGui.raw) {
-        if (hid::isModifierKeyActive(k))
-          ::LEDControl.setCrgbAt(r, c, highlight_color);
-        else
-          ::LEDControl.refreshAt(r, c);
-      } else if (k.flags == (SYNTHETIC | SWITCH_TO_KEYMAP)) {
-        uint8_t layer = k.keyCode;
-        if (layer >= LAYER_SHIFT_OFFSET)
-          layer -= LAYER_SHIFT_OFFSET;
-
-        if (Layer.isOn(layer))
-          ::LEDControl.setCrgbAt(r, c, highlight_color);
-        else
-          ::LEDControl.refreshAt(r, c);
+      Key k = Layer.lookup(r, c);
+
+      if (::OneShot.isOneShotKey(k) ||
+          (k.raw >= Key_LeftControl.raw && k.raw <= Key_RightGui.raw) ||
+          (k.flags == (SYNTHETIC | SWITCH_TO_KEYMAP))) {
+        uint8_t coords = r * COLS + c;
+        mod_keys_[mod_key_count_++] = coords;
       }
     }
   }
 
   return EventHandlerResult::OK;
 }
 
+EventHandlerResult ActiveModColorEffect::beforeReportingState() {
+  for (uint8_t i = 0; i < mod_key_count_; i++) {
+    uint8_t coords = mod_keys_[i];
+    byte c = coords % COLS;
+    byte r = (coords - c) / COLS;
+
+    Key k = Layer.lookup(r, c);
+
+    if (::OneShot.isOneShotKey(k)) {
+      if (::OneShot.isSticky(k))
+        ::LEDControl.setCrgbAt(r, c, sticky_color);
+      else if (::OneShot.isActive(k))
+        ::LEDControl.setCrgbAt(r, c, highlight_color);
+      else
+        ::LEDControl.refreshAt(r, c);
+    } else if (k.raw >= Key_LeftControl.raw && k.raw <= Key_RightGui.raw) {
+      if (hid::isModifierKeyActive(k))
+        ::LEDControl.setCrgbAt(r, c, highlight_color);
+      else
+        ::LEDControl.refreshAt(r, c);
+    } else if (k.flags == (SYNTHETIC | SWITCH_TO_KEYMAP)) {
+      uint8_t layer = k.keyCode;
+      if (layer >= LAYER_SHIFT_OFFSET)
+        layer -= LAYER_SHIFT_OFFSET;
+
+      if (Layer.isOn(layer))
+        ::LEDControl.setCrgbAt(r, c, highlight_color);
+      else
+        ::LEDControl.refreshAt(r, c);
+    }
+  }
+
+  return EventHandlerResult::OK;
+}
+
 }
 }
 

src/kaleidoscope/plugin/LED-ActiveModColor.h

@@ -20,6 +20,8 @@
 #include <Kaleidoscope.h>
 #include <Kaleidoscope-LEDControl.h>
 
+#define MAX_MODS_PER_LAYER 16
+
 namespace kaleidoscope {
 namespace plugin {
 class ActiveModColorEffect : public kaleidoscope::Plugin {
@@ -30,6 +32,11 @@ class ActiveModColorEffect : public kaleidoscope::Plugin {
   static cRGB sticky_color;
 
   EventHandlerResult beforeReportingState();
+  EventHandlerResult onLayerChange();
+
+ private:
+  static uint8_t mod_keys_[MAX_MODS_PER_LAYER];
+  static uint8_t mod_key_count_;
 };
 }
 }